Although the AU caused by each of the three types of herpes viruses has a number of common features, each disease also has distinct features that should facilitate an accurate diagnosis.

No abstract

Human T cell leukemia virus type 1, also known as human T lymphotropic virus type 1 (HTLV-1), is a retrovirus that encodes a reverse transcriptase, which translates viral RNA into a DNA provirus that is integrated into the host genome. The virus was found to be a causative agent of adult T cell leukemia/lymphoma (ATL) in the early 1980s, and was also found to cause the neurological disorder tropical spastic paraparesis (TSP)/HTLV-1-associated myelopathy (HAM) and the inflammatory disorder HTLV-1 uveitis in the mid 1980s and early 1990s, respectively. This article reviews eye diseases caused by or related to HTLV-1: HTLV-1 uveitis, ocular and systemic complications of HTLV-1, keratoconjunctivitis sicca, interstitial keratitis, and ATL.

Rationale:There are roughly 5 to 10 million persons infected with human T-lymphotropic virus type 1 (HTLV-1) worldwide, and the safety of treating this population with biologics remains poorly understood.Patient concerns and diagnosis:An HTLV-1-infected 66-year-old female with HTLV-1 uveitis (HU) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Her HU had been in remission and her HAM/TSP symptoms had been managed effectively with oral steroids for years. However, she developed severe rheumatoid arthritis (RA) after failing to respond well to conventional anti-rheumatic agents.Interventions:She was administered two intravenous 8mg/kg doses of the biologic tocilizumab.Outcomes:Subsequently, her RA symptoms resolved, but she suffered a recurrence of HU and exacerbation of HAM/TSP symptoms. When she was switched back to steroid-based treatment, HU and HAM symptoms both improved, but RA symptoms again worsened. Finally, an attempt to substitute the biologic abatacept and reduce the steroids failed when HAM/TSP symptoms again became aggravated.Lessons:To the best of our knowledge, this represents the first report worldwide of a biologic aggravating HTLV-1-associated conditions. This report suggests that caution is advised when using biologics to treat HTLV-1-infected patients, though further research is required to clarify the situation.